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Power-Efficient Access-Point Selection for Indoor Location Estimation
July 2006 (vol. 18 no. 7)
pp. 877-888
An important goal of indoor location estimation systems is to increase the estimation accuracy while reducing the power consumption. In this paper, we present a novel algorithm known as CaDet for power-efficient location estimation by intelligently selecting the number of Access Points (APs) used for location estimation. We show that by employing machine learning techniques, CaDet is able to use a small subset of the APs in the environment to detect a client's location with high accuracy. CaDet uses a combination of information theory, clustering analysis, and a decision tree algorithm. By collecting data and testing our algorithms in a realistic WLAN environment in the computer science department area of the Hong Kong University of Science and Technology, we show that CaDet (Clustering and Decision Tree-based method) can be much higher in accuracy as compared to other methods. We also show through experiments that, by intelligently selecting APs, we are able to save the power on the client device while achieving the same level of accuracy.

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Index Terms:
Data mining in mobile wireless networks, power efficient computation.
Yiqiang Chen, Qiang Yang, Jie Yin, Xiaoyong Chai, "Power-Efficient Access-Point Selection for Indoor Location Estimation," IEEE Transactions on Knowledge and Data Engineering, vol. 18, no. 7, pp. 877-888, July 2006, doi:10.1109/TKDE.2006.112
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